PHP draws ECG shape curve statistical chart [source code]_PHP tutorial

Let’s take a look at the final effect:

The following is the PHP code:

<ol class="dp-xml">
<li class="alt"><span><span>/****************************** </span></span></li>
<li><span>* Line chart generation function </span></li>
<li class="alt"><span>***********************************/  </span></li>
<li>
<span>function line_stats_pic($value_y,$width,$high,$</span><span class="attribute">strong</span><span>=</span><span class="attribute-value">1</span><span>,$</span><span class="attribute">fix</span><span>=</span><span class="attribute-value">0</span><span>){  </span>
</li>
<li class="alt"><span>//y值处理函数  </span></li>
<li><span>function line_point_y($num,$width,$high,$max_num_add,$min_num_add,$y_pxdensity){  </span></li>
<li class="alt">
<span>    $</span><span class="attribute">return</span><span>=$high-floor(($num-$min_num_add+$y_pxdensity)/(($max_num_add-$min_num_add)/$high));  </span>
</li>
<li><span>    return $return;  </span></li>
<li class="alt"><span>}  </span></li>
<li><span> </span></li>
<li class="alt"><span>//参数处理  </span></li>
<li>
<span>$</span><span class="attribute">allnum</span><span>=</span><span class="attribute-value">sizeof</span><span>($value_y);  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute-value">max</span><span class="attribute">max_num</span><span>=max($value_y);                            //最大值  </span>
</li>
<li>
<span>$</span><span class="attribute-value">min</span><span class="attribute">min_num</span><span>=min($value_y);                            //最小值  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">limit_m</span><span>=$max_num-$min_num;                        //极差  </span>
</li>
<li>
<span>$</span><span class="attribute">max_num_add</span><span>=$max_num+$limit_m*0.1;                //轴最大值  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">min_num_add</span><span>=$min_num-$limit_m*0.1;                //轴最小值  </span>
</li>
<li>
<span>$</span><span class="attribute">limit</span><span>=$max_num_add-$min_num_add;                 //极差-坐标轴y  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">y_pxdensity</span><span>=($max_num_add-$min_num_add)/$high;    //y轴密度  </span>
</li>
<li>
<span>$</span><span class="attribute">x_pxdensity</span><span>=</span><span class="attribute-value">floor</span><span>($width/$allnum);                //x轴密度  </span>
</li>
<li class="alt"><span>reset($value_y);                                 //将数组指针归零  </span></li>
<li>
<span>$</span><span class="attribute">i</span><span>=</span><span class="attribute-value">0</span><span>;  </span>
</li>
<li class="alt"><span>foreach($value_y as $val){  </span></li>
<li><span>    $point_y[$i]=line_point_y($val,$width,$high,$max_num_add,$min_num_add,$y_pxdensity);  </span></li>
<li class="alt"><span>    $i++;  </span></li>
<li><span>}</span></li>
<li class="alt">
<span>$</span><span class="attribute">zero_y</span><span>=</span><span class="attribute-value">line_point_y</span><span>(0,$width,$high,$ max_num_add,$min_num_add,$y_pxdensity); //Y value of zero point </span>
</li>
<li>
<span>$</span><span class="attribute">empty_size_x</span><span>=(strlen($max_num) </span><span class="tag">></span><span> strlen($min_num) ? strlen($max_num) : strlen($min_num))*5+3; //Left blank </span>
</li>
<li class="alt"><span> </span></li>
<li><span>//The image stream starts </span></li>
<li class="alt"><span>header("Content-type:image/png"); </span></li>
<li>
<span>$</span><span class="attribute">pic</span><span>=</span><span class="attribute-value">imagecreate</span><span>($width+$empty_size_x+10,$high+13); </span> </li>
<li class="alt">
<span>imagecolorallocate($pic,255,255,255);                                                                                                                                                                                                                                                        ></span>imagecolorallocate</li>
<li>($pic,30,144,255); //Line color <span></span><span class="attribute"></span>$<span></span>color_2<span class="attribute-value"></span>=<span></span>imagecolorallocate</li>
<li class="alt">($pic,0,0,0); //Black <span></span><span class="attribute"></span>$<span></span>color_3<span class="attribute-value"></span>=<span></span>imagecolorallocate</li>
<li>($pic,194,194,194);//Gray <span></span><span class="attribute"></span>//Draw grid <span></span><span class="attribute-value"></span>imagesetthickness($pic,1); //Grid line width <span></span>
</li>
<li class="alt">$<span></span>y_line_width</li>
<li>=<span></span>floor</li>
<li class="alt">($width/100);                                             //Number of vertical grid lines <span></span><span class="attribute"></span>$<span></span>y_line_density<span class="attribute-value"></span>= $<span></span>y_line_width</li>
<li>==0 ? 0 :floor($width/$y_line_width); //Vertical grid line density <span></span><span class="attribute"></span>$<span></span>point_zero_y<span class="attribute"></span>=$zero_y <span></span>></li>
<li class="alt"> $high ? $high : $zero_y; <span></span><span class="attribute"></span> imagestring($pic,1,$empty_size_x-1,$high+4,"0",$color_2); //Zero point axis mark <span></span><span class="tag"></span>for($<span></span>i</li>
<li>=<span></span>1</li>
<li class="alt">;$i <span></span>= $y_line_width;$i++){                Vertical grid lines <span></span><span class="attribute-value"></span> imagesetthickness($pic,1); //Grid line width <span></span><span class="tag"></span> imageline($pic,$y_line_density* $i+$empty_size_x,0,$y_line_density*$i+$empty_size_x,$high,$color_3); <span></span>
</li>
<li> imagesetthickness($pic,2); //Axis point line width <span></span>
</li>
<li class="alt"> imageline($pic,$y_line_density*$i+$empty_size_x,$point_zero_y-4,$y_line_density*$i+$empty_size_x,$point_zero_y,$color_2); <span></span>
</li>
<li> imagestring($pic,1,10 <span>
</span>
</li>
<li class="alt">http://www.bkjia.com/PHPjc/486091.html<span></span>www.bkjia.com</li>
<li>true<span>http: //www.bkjia.com/PHPjc/486091.html<p align="left"></p>
<div style="display:none;">TechArticle<span id="url" itemprop="url"></span>Let’s take a look at the final effect: The following is the PHP code: /******************************** *Line chart generation function************************ *************/ functionline_stats_pic($value_y, $width,$high,$ str...<span id="indexUrl" itemprop="indexUrl"></span><span id="isOriginal" itemprop="isOriginal"></span>
<span id="isBasedOnUrl" itemprop="isBasedOnUrl"></span>
</div></span>
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